Thomas wallace



(No Model.)

T. WALLACE.

TELErHoNE. 4

No. 312,533. Patented Feb. 17, 1885.

IEEE/@ EU/Tg2@ .3o r the inductorium into comparatively strong or 4o f f tion.

@NITE STATES ArnNT @FFICE A THOMAS WALLACE, `OF NEW YORK, 'N'. Y.

A TELEPHONE.

SPECIFICATION forming part of Letters Patent No. 312,533, dated February 17, 1885.

` Application Filed January 8, 1885. (No model.) Patented in Canada JnnuarySO, 188:3, No 21,004.

To @ZZ whom it may concern.-

Be it known that I, THOMAS WALLACE, a citizen of the United States, residing in the city, county, and State of New York, have invented certain new anduseful Improvements in Telephones, of which thefollowing is a or sound vibrations such as are caused by the utterance of speech. In someinstances their use as transmitters to translate the air` or sound vibrations intoelectricalvariations has been suggested, but they have been found to produce but feeble results, and their use as both transmitters and receivers has been abandoned.

, The electric or battery telephonehas been almost universally used as a transmitter, and wheneverit becomes necessary to send messages any considerable distance the transmitter-instrument is included in the primary of an inductorium the secondary of which is included in the. line-circuit. In this way the variations in the comparatively weak galvanic currenthave been transformed by the use of intense secondary current-s, which have been received and translated into speech by a magneto-receiver. Thisnecessitates not only the use at each station of two separate telephonie` instruments of di'erent classes, each ot' which is more or less complicated and expensive, but also a local battery and an inductorium, which also add greatly to the expense, and are extremely liable-to derangement and destruc- There are thus to be found in the ordinary telephonie line or system-as for the connection of two stations, for instancetwo local batteries, two battery transmitting -instruments of greater or less complexity of construction, two magneto receiving-instru ments, each consisting ot' a magnet-core, helix, and diaphragm, two expensive in'ductioncoils, including the two primary and the line circuits and the necessary signaling-instruments, if used.

The object of my invention is to produce an electric telephonie system embracing neither One of the earliest forms of speakingtelef-` "5 phones consisted of astandard having two pro-` jecting lugs ot' carbon, with a block or pencil of carbon having pointed ends fitting into recesses in the carbon. lugs on the standard. t This instrument, with various modilications and multiplications,has been used successfully as a transmitting-instrument, and I have found Y that by changing the construction of such instrument in a manner substantially as pointed ont hereinafter, and connecting it up in line, v

as hereinafter indicated, itmaynotonlybe used as a transmitter, but as a successfutreceiver, and this without anyof the usual ad:

juncts of a system, as heretofore pointed out, y, exceptachargedlinegand I havefurtherfound that such an instrument requiresnofiineadl just ment and regulation, but once constructed and set up is practically self regulating and adjusting, and equally adapted to operate both as a transmitter and receiver instrument.

I will now proceed to describe my invention with reference to the accompanyingdraw ings, which forinpart of this specification, 'in Which- Figure lis aplan view ofthe principalparts Il" of a telephone embodying `myinvention. Eig`. 2 is a section of another formof instrument, Fig.3 is a diaphragm of a line or system fortwo stations, showing my invention, and disclosing still other forms oftelephonicinstruments emA bodying the same; and Fig. 4 is a diagram showing the use of one telephone as both the transmitting and receiving instrument at each station. Similar letters" parts in all thelgures.` :v

To some sort. of` a resonant body, A, arefconf nected or attached two studs,:projetionsgor bearin'gpieces, B B', of carbon or similar substance, having sockets or bearings C C formed therein. Fitting into these sockets or bearof sfera@ IOO 2 v lassa A strument, and the details may be varied in i 5 many ways without departing` from my inven- `Itth'estuds or projections B I3 are representedf'asbeing mounted upon a disk- V'shaped sounding*board orresonator, which 2o may be of any material preferred, and this may be used in any suitable or conveniently.

shaped case, as shown in the receiver R in Fig. 3.

In Fig. 2 the bearings B B are shown as :mounted upon studs G G, fixed to the sides bf,aTcup-shapeld resonating-case, H, having the usual mouth or ear piece, I, and having an opening, J, to'which a tube,`T, may be applied, sothat'the'sameinstrument may be used rf e' f'er and transmitter without change eio'ffpo'si't on.y

In Fig. 3 the contact-pieces are shown as supported upon a rectangular plate, K,`of wood or similar material, carried in a suitable 'framehaving convenient binding-posts. From 'this it will be readily understood that it is imla't'eri'al'to the 'essence' of this part of my in- 'ventioii in'what form or construction of case Vthe e'on-tactpi'eces may be carried, it only be- 4o: ing necessary-'that fsome efsonafnt;material.A f I' y 'f "Anfin'"t'ru'meiit as thus constructed has been found to work practically as both a transmitter and receiver, and in Fig I have illustrated one manner of connecting such instruments up in a system or line, which will be readily understood by electricians. It will be seen U- that the galvanic circuit passes from one pole JVSfthe*battery "through-the studs B B and part thereofbe of V carbon rod I) directly to line, the instrument i ji end'e'd 'to be used asa receivcr being in a an'chcircuit aroundthe transmitter and bat- I, SuchA an arrangement 'necessitates the fnseof'a batteryA at each end of the line; but the receiving-instrument maybe placed directly in the main circuit, as in the case where a single instrument is used both as a transmitter and a receiver, as indicated in Fig. 4. It will thus be seen that I produce a complete 6o t lephonic line or system without the use of ymagnet or'coils, ilocal-battery circuits, or inductoriums, and that owing to the simple 0V st'ic'tion of {instruments 'no fine adjust- I have found that I can usear'eIatively- 65 strong battery-current, and .amthereby enabled to transmit speech over long distances, and this without thc usual rattling often found in transmitters of this character, and thatthe disturbances attributed to induction, &c., are 7 practically nullified.

I have also found that the instrument is very effective as a receiver when the bar or studs or both are composed of comparatively soft and porous carbon in contradistinction to hard compact carbon. 'f y I am aware that the use of an instrument consisting of a diaphragm'forming one electrode and having a pointed electrode bearing against its center has been suggested as. both 8o a transmitting and Areceiving instrumet,.and I make no claim to such construction.

Vithout limiting vmyself' :to:any. particular details of construction, \VhatI:claim vis-.

l. A telephone-instrn-ment .`consisting]v of.,a resonant body, a bar of carbon.s-upportedain carbon-bearings, anda weighted covering or casing for said bar, substantially as described.

2. A telephonie receiver consisting. of a` weighted bar of carbon supported in carbon- 9o bearings, in connection with a resonating body, substantially as described.

3. A combined transmitting and receiving telephone-instrument, consisting ofa rod of carbon supported in carbon-bearings,fin, C011- nection with a resonatingLv body and :suitable mouth and ear pieces, sub'stantially-asydev scribed. Y fil-L y i,

4. A contact-piece fortelephones, consisti ng v of a bar or rod of carbon or similar low conroo ducting material having a coveringor casing of metallic foil, substantially as described;

5. A telephonie system orliue embracinga galvanic circuit including two or moretelephoneinstrumen ts, each consisting of: a weighted carbon bar supported in bearings, inuco'nnection with a resonant body, and adapted-to act both as a transmitterand receiven-whereby speech may be transmittedand receivedn'witlr out thc use of 1nagnets,.coils, `orinductoriums, 1ro substantially as set forth. f

6. The combination,with ak charged linecircuit, of atransmitter consisting, essentially, of a carbon rod supported incarbon-.bearings 2f upon a resonant body arranged in the` main 1x5 galvanic circuit, and a receiver consistingof a similar carbon rod supported in carbon-.bearings, and connected` to a resonantbodyfin-a branch circuit aroundv the transmitterj,vl ulb-cg'. stantially as describeduw" f In testimony wherc'ofI havfesigned my name to this specification in the presence of tw'o subscribing witnesses.

THOMAS IVALLACE. 

